External-cavity birefringence feedback effects of microchip Nd:YAG laser and its application in angle measurement
Ren Cheng(任成)†, Tan Yi-Dong(谈宜东), and Zhang Shu-Lian(张书练)
State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments \& Mechanology, Tsinghua University, Beijing 100084, China
Abstract External-cavity birefringence feedback effects of the microchip Nd:YAG laser are presented. When a birefringence element is placed in the external feedback cavity of the laser, two orthogonally polarized laser beams with a phase difference are output. The phase difference is twice as large as the phase retardation in the external cavity along the two orthogonal directions. The variable extra-cavity birefringence, caused by rotation of the external-cavity birefringence element, results in tunable phase difference between the two orthogonally polarized beams. This means that the roll angle information has been translated to phase difference of two output laser beams. A theoretical analysis based on the Fabry--Perot cavity equivalent model and refractive index ellipsoid is presented, which is in good agreement with the experimental results. This phenomenon has potential applications for roll angle measurement.
Received: 24 November 2008
Revised: 23 March 2009
Accepted manuscript online:
PACS:
42.55.Rz
(Doped-insulator lasers and other solid state lasers)
Fund: Project
supported by the National Natural Science Foundation of China (Grant
No 50575110).
Cite this article:
Ren Cheng(任成), Tan Yi-Dong(谈宜东), and Zhang Shu-Lian(张书练) External-cavity birefringence feedback effects of microchip Nd:YAG laser and its application in angle measurement 2009 Chin. Phys. B 18 3438
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